I noticed the other day that I hadn’t posted anything on this site for nine months! There are a few reasons for this; following my contraction of Covid-19, I found it difficult to muster enthusiasm for hobbies, something that is only now just beginning to come back. A more pressing obstacle over the last few months has been the renovation of my house with almost all of my belongings being held in storage. My workbench is just now slowly begining to take shape again, albeit in slightly reduced form. Finally, looming redundancy means I am being very careful with my money.
This last point is perhaps most salient here. I often buy/build projects of which only a few I have any real need for, the project itself often seems to be the prime motivation rather than the actual physical end product – I am sure I am not alone in this. A friend asked me this week if I had any ideas for a simple, cheap streaming audio setup for his garage. Whilst I was thinking about this and unpacking some of my electronics boxes, I came across various items that could be used rather than purchasing something new. There was an amplifier bought for a project for my daughter which never came to fruition, a Raspberry Pi Zero and DAC HAT which was bought for another amplifier but which proved problematic to implement and some speakers from an old JVC mini sound system which had expired.
The makings of something is here although what form the final project will take, I’m not sure. My friend always has various bits of scrap wood and metal floating around so we should be able to knock something together. Even if I bought all of these components new, this would still be a very cheap route to obtain an acceptable kitchen/garage type setup. The components for a complete build with approximate costs are detailed below:
GHX TPA3116 Class D amplifier board from Aliexpress with Bluetooth 5 £16. I have a 2.1 version but standard stereo versions are available
Power supply. I used a 19V laptop charger as I collect these from friends when they replace their laptops but expect to pay £10-15
Raspberry Pi Zero WH – £13
Micro SD card for Pi operating system (8GB minimum you can get Sandisk 32GB for about £6)
DAC HAT for Pi Zero – I had an IQAudio Pi DAC Zero HAT which cost £18 but these are no longer available. Alternatives include offerings from JustBoom and Allo.
Cable to connect Pi Zero to amplifier. The GHX amp has a 3.5 mm input and the DAC has two RCA outputs so a 3.5mm to RCA is needed for this setup, I used this basic cable from Amazon and it’s very nicely made (£5 when I bought it but slightly more expensive now).
Whatever speakers you have!
Whilst the GHX amp has Bluetooth, I added the Pi streamer option as Bluetooth can deplete the phone battery more quickly than streaming over WiFi and having both options can be useful if one or the other is problematic in connecting.
All in all, you could get something similar for about £70 if you had to purchase it all (speakers not included in this) but I suppose the purpose here was to reuse what was available.